Not Applicable.
1. Field of the Invention
The present invention relates to a tubular element for drawing liquid from a container by applying a vacuum at one of its ends, designed to pass through an orifice or an elastically extendable inlet conduit of the said container, the cross section of this tubular element being sized to be contiguous with the edge of this orifice or with the wall of this conduit which comprises means projecting from one portion of its outer tubular surface and shaped for allowing the said portion to pass through the said orifice or the said conduit from the outside towards the inside of the container and to counter its passage in the opposite direction.
2. Description of the Prior Art
There are a number of containers in existence, especially ones in the form of bags used most particularly for packaging drinks, designed to enable the drink to be consumed directly from the bag by sucking it up using a straw. These bags generally present a hygiene problem which results from the fact that the straw can be removed and replaced into the bag, so that there is a risk of the user introducing a dirty straw back into the wrapping. This risk is all the greater since the user is very often a child and even a very small child to whom the idea of hygiene could be very vague.
Furthermore, the end of the straw designed to be introduced into the bag is generally cut into a bevel thus making a pointed end, in order to perforate a closure designed to seal the bag before its first use. By allowing the free withdrawal of this straw from the bag, the user runs the risk of injuring himself with the bevelled end which is relatively hard and capable of puncturing. Once again, this risk is all the greater when the bag is in the hands of a young child.
A straw has already been proposed in DE 297 10 651 for drawing a drink from a container by sucking, having a bulge of which the cross section increases gradually and ends by returning suddenly to the initial section of the straw. In this way, the straw can be pushed through an orifice in the container, one of the elements (the orifice or the bulge) being elastically deformable, so that the front part of the bulge whose cross section increases gradually can pass through the orifice. The sudden narrowing of the bulge which is at the rear then prevents the straw from coming back out of the orifice. As the front end of such a straw is designed to be inserted through an orifice closed by a perforable closure, it has to be sharp, therefore bevelled, which means that if the straw is pulled out of the orifice, which is still possible, it remains dangerous.
Another solution fairly similar to the previous one was described in U.S. Pat. No. 5,114,074, and the same remarks as for the previous solution are applicable in this case.
Furthermore, when such a straw is used with a bag controlled by a valve formed by a channel made between two lines of welding joining two superposed films together, the cutting bevelled end of the straw inserted in this channel presents the risk of damaging this valve after repeated movements of insertion and withdrawal of the straw intended, respectively, to open and to close this valve.
The object of the present invention is to remedy, at least in part, the aforementioned drawbacks and risks.
To this end, the subject of this invention is firstly a tubular element of the aforementioned type.
The subject of this invention is also a process or manufacturing this tubular element.
According to a preferred embodiment of the invention, the annular bulge is made from one portion of the end of the tubular element in a thermoformable material, turned back on itself towards the outside. The end with the truncated cone shaped outer surface is then formed on the end of this turned-back portion.
The end of the turned-back portion of the tubular element is brought back along the straw and forms an annular bearing surface on the outside of the tubular element, serving as a stop to stop this tubular element when there is a desire to withdraw its annular bulge from an orifice or from a conduit of a cross section corresponding to the normal cross section of this tubular element after having put it in through this orifice or this conduit. On the contrary, the truncated cone shaped portion formed at the front of this annular bulge enables a centrifugal force to be exerted on the edges of the orifice or the wall of the conduit made from an elastically extendable material in order to expand it and allow the insertion of the tubular element into the bag and allow this orifice or this conduit to close back up on this tubular element, after its bulge has passed through.
As may be realised, the preferred embodiment of the invention allows the provision of a means which effectively prevents the withdrawal of the tubular element, while at the same time solving the problem concerning the cutting end of the straw, since this cutting end is turned back on itself and since the new end is no longer bevelled and is therefore neither pointed nor cutting, the formation of the truncated cone shape by hot moulding of the turned-back part of the tubular element producing a blunt edge.
The appended drawing illustrates, schematically and by way of example, one embodiment of the tubular element, that is the subject of the present invention, and one embodiment of its process of manufacture.